Jackson explains that Apple prefers to buy power from renewable energy projects where the company played some role–by either investing capital up front or committing to buying the power produced there for a long time, sometimes decades.

In 2015, Apple started a program to move suppliers toward green energy. Last year, 14 such companies pledged to work toward running the parts of their operations that serve Apple on 100% renewable energy. Today, Apple announced that another nine of its suppliers have promised to reach this goal.